MOSCOW, Aug 7 (Reuters) - A native of eastern Ukraine may replace a Russian as leader of the separatists there, sources familiar with the situation told Reuters, a move aimed at blunting Western accusations that the rebellion is being run by Moscow.

The United States and the European Union have slapped sanctions on Russia, accusing it of arming the rebels in the east of the former Soviet republic. Moscow denies the accusation and has imposed its own sanctions in retaliation.

Aleksander Borodai, current head of the self-proclaimed "Donetsk People's Republic" (DNR), is one of several Russian nationals that have taken top roles among the pro-Russia rebels .

The sources said he may soon be replaced by a native of Donetsk, Alexander Zakharchenko, who heads a heavily armed rebel unit called Oplot.

"He is being named to beef up the military wing," one source said.

Zakharchenko, in his late 30s, was among the first separatists who occupied the regional administration building in Donetsk when pro-Russian crowds captured it in March following the ousting of a Moscow-allied president in Kiev.

Andrei Purgin, one of the DNR leaders, said that change was being considered but had not been formally approved as yet.

One of Zakharchenko's aides said: "It's more likely to happen than not to happen." (Reporting by Anton Zverev; Additional reporting and writing by Gabriela Baczynska; Editing by Robin Pomeroy)